Mobile devices are widely employed for communications, computing, and social media. They include camera systems—often at least two, a rear-facing and front-facing—for the capture of images. These camera systems can also be regarded as input devices for the communication between the user of the mobile device, and the mobile device's software and systems. One means of communication these camera systems can enable is recognition of gestures in space and time implemented by the user of the mobile device.
The consumption of electrical power by mobile devices is an object of continued focus, with the goal being to minimize power and, for a given battery, extend the operating lifetime of the device between required charges. Minimizing the consumption of electrical power in electronic products is of critical and ever-growing importance. As one example of a means of minimizing power, it is possible to regulate the brightness of a display on a mobile device in order to use only the necessary power. Mobile devices often employ sensors that provide dimming of the display brightness in view of sensed information regarding the level of ambient lighting. Moreover some devices use multiple sensors and different wavelengths to enable functions such as proximity sensing and basic gesture recognition.